Elastic-fluid turbine



April 15 1924. 1,490,755

H. L. WIRT ELASTIC FLUID TURBINE Filed Sent. 12: 1922 'lhVento HarrisonLN/ir't,

Patented Apr. 15, 1924.

ELENHTE. STATES ?TET QFICE.

EARRISON LORING W'IRT, F SOHENECTADY, NEW YORK, ASSIGNOR TO GENERALELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELASTIC-FLUID TURBINE.

Application filed September 12, 1922. Serial No. 587,809.

T 0 all whom it may concern:

Be it known that I, HARRISON L. TIRT, a citizen of the United States,residing at Schenectady, county of Schenectady, State of New York, haveinvented certain new and useful Improvements in Elastic-Fluid Turbines,of which the following is a specification.

The present invention relates to elastic fluid turbines and particularlyto the stationary fluid directing elements of such turbines. The objectof my invention is to provide an improved fluid directing elementstructure by the use of which a better efiiciency is obtained than withstructures heretofore in commonuse, and for a consideration of what Ibelieve to be novel and my invention attention is directed to theaccompanying description and the claims appended thereto.

While my invention is applicable to turbines of either the impulse typeor the reaction type it is especially well adapted for use with theformer and I have accordingly illustrated and described it as applied toan impulse turbine. It is to be understood, however, that the inventionis not limited thereto.

In the drawing, Fig. 1 is a diagrammatic view showing a cylindricalsection of a turbine structure having fluid directing elements embodyingmy invention, the passages being brought into the same horizontal plane,and Fig. 2 is a detail radial sectional view.

Referring to the drawing, 5 indicates a series of fluid-directingpassages usually termed nozzles in connection with an imulse machine.These nozzles are defined 4 y radially inner and outer walls 6 and 7 andnozzle plates or partitions 8. Walls 6 and 7 are usually in the form ofannular members with the nozzle partitions arranged between them andsuitably connected thereto. Adjacent the nozzle partitions are rings ofbuckets or blades 9 carried by the rotor element of the turbine. In thepresent instance they are shown as being carried by wheels 10. Elasticfluid enters the nozzles as indicated by the arrow X and is directed bythe nozzles against the blades or buckets, the direction of rotationbeing indicated by the arrow Y. In the following specification, I termthe nozzle-defining surface 11 the rear wall of the nozzle and thenozzledefining surface 12 the front wall of the nozzle.

The structure and operation of a turbine as described above is wellunderstood and the arrangement is to be taken as typical of any suitableturbine structure. Between the exit ends of the fluid-directingelements, plates or partitions and the inlet edges of the rotatingblades or buckets there is always a clearance which may be of the orderof 0.20 inches for example, and it will be clear that there are spacesrepresented by continuations of the plates or partitions up to theentrance edges of the blades or buckets towhich .no elasticv fluidpasses directly from the fluid-directing passages. In the drawing, thesespaces are represented by the areas contained within the dottedparallelograms 13. p

More particularly the object of my inventionis to provide a structurewherein the elastic fluid in leaving the fluid-directing passages willbe caused to fill the spaces 13 so there will be a substantiallycontinuous solid stream of elastic fluid entering the blades or buckets.To -this end I provide the front wall 12 of each fluid-directing passagewith a rounded projection 14k located preferably just beyond the planeof the exit end of the passage, which plane is indicated by the line A,and in such a position that it serves to deflect elastic fluid intoSpaces13. This deflecting of the elastic fluid stream while it serves tofill spaces 13 does not af-v feet the direction of the flow because suchflow is guided and directed by, that portion of the front wall of thefluid passages which lies beyondthe plane of the exit end as regards thedirection of flow. This is due to the fact that the instant the fluidstream tends to leave such guiding surface a region of lower pressure isformed on theguiding surface which tends to restore the stream to theguiding surface and makes it exit from the nozzle at the proper angle.

By the use of a fluid-directing structure embodying my invention I amenabled to provide a structure which will supply a continuous solidstream of elastic fluid to the entrance edges of the blade ring orbucket ring. This means that the blade ring or bucket ring will becontinuously supplied with elastic fluid so that the efliciency will beimproved. Furthermore, since the regions represented by parallelograms1,3 are filled with elastic fluid, the formation of eddy currents insuch spaces is prevented. When such spaces are not filled, eddy currentsmay form in them, disturbing the flow and effecting losses inefficiency.

In accordance with the provisions of the patent statutes I havedescribed the principle of operation of my invention, together with theapparatus which I now consider to represent the best embodiment thereof,but I desire to have it understood that the apparatus shown is onlyillustrative and that the invention may be carried out by other means.

What I claim as new and desire to secure by Letters Patent of the UnitedStates, is

1. An elastic fluid turbine comprising a rotor having one or more ringsof blades thereon, and fluid-directing elements for directing elasticfluid to the blades, there being clearance spaces between the exit endsof the fluid-directing elements and the entrance edges of the blades,characterized by the fact that the said fluid-directing elements areprovided with guiding surfaces immediately following the plane of thenozzle throat which serve to deflect elastic fluid into such spaces.

2. In an elastic fluid turbine, walls forming fluid-directing passages,the front walls of said passages being provided with projectionsimmediately following the plane of the nozzle throat which serve todeflect the stream of elastic fluid toward the rear walls.

3. In an elastic fluid turbine, walls forming fluid-directing passages,the front walls of said passages being provided with projections locatedjust beyond the exit planes of the passages which serve to deflect thestream of elastic fluid toward the rear walls.

4. An elastic fluid turbine having blades, and nozzles for directingelastic fluid to the blades characterized by the fact that the frontwalls of the nozzle partitions are provided with rounded projectionswhich serve todeflect elastic fluid toward the rear walls.

5. An elastic fluid turbine having blades,

and nozzles for directing elastic fluid to the blades, there beingclearance spaces between the exit ends of the nozzle partitions and theentrance edges of the blades, characterized by the fact that the nozzlepartition which forms the front wall of each nozzle passage is providedwith a rounded projection which serves to deflect elastic fluid into theclear a ance space at the end of the nozzle partition which defines therear, wall of such nozzle.

In witness whereof, I have hereunto set my hand this 11th day ofSeptember, 1922.

HARRISON LORING WIRT.

